Questions tagged [brms]
brms is an R package interfacing stan for Bayesian analysis
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How to fit a Bayesian model to a mixture of Beta and One-Zero inflated data?
I have very noisy data, which I believe is created through interactions of multiple physical processes. In the mapping $Y = f(X),$ $Y$ is a ratio $[0, 1]$ and $X \ge 0.$ While $Y$ is a function of $X,$...
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post-hoc test for multinomial logistic regression brm model (categorical response)
I apologise as I am very new to this package and I really appreciate any help I can get.
I have a brms model with a categorical response variable (Species) with the ...
Leo
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1
answer
55
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The default covariance structure implicitly assumed in the brms formula
Background: The brms official page provides the following example code to illustrate the usage of the package:
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Estimating markov transition matrix using total elevator "ups" and "downs" by floor
I have data on elevator presses and I am hoping to use them to estimate a Markov transition matrix, so I can ultimately estimate how frequently people go to different floors.
For each floor from 1-4, ...
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Inconsistent posterior from hierarchical survival model
I asked about this question on Stan forum but no one replied so dual posting here. I'd really appreciate some insight, as I'm completely stuck.
I’m trying to do hierarchical survival modeling using ...
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Calculating contrasts of marginal effects with marginaleffects for brms model
I have fitted a logistic model with brms and want to calculate the average marginal effects (AMEs).
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Interaction: Posterior comparison brms, difference between as_draws, and posterior_predict. Is it correct to interpret posterior_predict instead?
I have an interaction effect in my model, and I want to extract the posterior of each of my parameter in order to compare them and make inference about them. I couldn't simply use the as_draws() ...
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Likert scale study - ordinal regression model
My linguistics rating experiment contains 36 stimuli in total for rating. There are 6 themes (e.g. doctor, farm, etc), and each theme has 3 conditions (good, bad, mixed), and each condition has 2 ...
Joy Fu
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Setting priors for categorical variables in bayesian multilevel model analysis with BRMS package (repost)
I am reposting the same question that I made on Stack Overflow. I am new with Bayesian analysis methods and I am still struggling understanding some concepts regarding priors. I am running a model ...
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Include error on the predictor from mean and asymetric credible interval
I am doing non-linear models with brms. My model is :
...
Julien Beaulieu
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How to select a proper prior to control the time dependent structure of variable?
I am new in analyzing RCT data and not familiar with the techniques that are always used in RCT analysis.
I am analyzing a dataset of a study: An RCT study with 50 participants; the data was collected ...
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Results dirichlet regression - brms vs DirichelReg comparison
I am new to Dirichlet regression, but I am trying to understand why model outputs are potentially different when I use two different R packages, and how I could interpret the slope and intercept ...
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Bayesian linear regression: How to enforce constraint on the sum of coefficients?
I have a linear regression problem in which my $X$ matrix is not full rank. Here is a small example:
$$X =
\left[\begin{array}{rrrr}
-1 & 0 & 0 & 1 \\
1 & 0 & -1 & 0 \\
0 &...
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How to improve bayesian logistic regression model with priors
I'm trying to fit a bayesian logistic regression model to calculate the expected goals (xG) of certain shootings data in football. My model has some simple features where I first fit a model with ...
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Is it possible to estimate effects using Bayesian modelling after matching?
I am following [Greifer 2023][1] to estimate the effect size after (genetic) matching, where I am using bootstrapping to estimate the confidence intervals. Since I have a hierarchical setup with ...
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